diff options
| author | Konstantin Khlebnikov <khlebnikov@yandex-team.ru> | 2017-11-02 17:07:05 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-11-04 22:34:52 +0900 |
| commit | 991a26af2e65e0422b2a899e373c0146f2436cae (patch) | |
| tree | f4bc9dcd39fd1d3e88d79446f9e7b6e727e074a2 /net/ipv4 | |
| parent | 9d917c207d6b212eb5fb4d8ca31826e5b75b4d28 (diff) | |
| download | linux-991a26af2e65e0422b2a899e373c0146f2436cae.tar.bz2 | |
tcp_nv: use do_div() instead of expensive div64_u64()
Average RTT is 32-bit thus full 64-bit division is redundant.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Suggested-by: Stephen Hemminger <stephen@networkplumber.org>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp_nv.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/net/ipv4/tcp_nv.c b/net/ipv4/tcp_nv.c index 0529e29e2941..0b5a05bd82e3 100644 --- a/net/ipv4/tcp_nv.c +++ b/net/ipv4/tcp_nv.c @@ -242,7 +242,7 @@ static void tcpnv_acked(struct sock *sk, const struct ack_sample *sample) struct tcp_sock *tp = tcp_sk(sk); struct tcpnv *ca = inet_csk_ca(sk); unsigned long now = jiffies; - s64 rate64 = 0; + u64 rate64; u32 rate, max_win, cwnd_by_slope; u32 avg_rtt; u32 bytes_acked = 0; @@ -284,8 +284,9 @@ static void tcpnv_acked(struct sock *sk, const struct ack_sample *sample) } /* rate in 100's bits per second */ - rate64 = ((u64)sample->in_flight) * 8000000; - rate = (u32)div64_u64(rate64, (u64)(avg_rtt ?: 1) * 100); + rate64 = ((u64)sample->in_flight) * 80000; + do_div(rate64, avg_rtt ?: 1); + rate = (u32)rate64; /* Remember the maximum rate seen during this RTT * Note: It may be more than one RTT. This function should be |